What are the best NPC housing designs for maximizing happiness in Terraria?

To maximize NPC happiness in Terraria, you need to understand the mechanics of the happiness system and how it affects NPCs. NPC happiness is determined by two main factors: the biome they live in and their neighbors. Each NPC has preferred biomes and neighbors, and being in a disliked biome or near disliked neighbors will lower their happiness. High happiness reduces the prices of items they sell and increases the chance of receiving special items like the Pylon system, which allows fast travel between biomes. Low happiness increases prices and prevents Pylon sales.

To start, you need to build suitable housing for your NPCs. Each NPC requires a room that is at least 6 blocks wide and 10 blocks tall, with walls, a light source, a table, a chair, and a door. The room must be fully enclosed and have a valid entrance. Once you have the basic housing set up, you can focus on optimizing their happiness.

First, place NPCs in their preferred biomes. For example, the Guide prefers the Forest biome, the Merchant likes the Forest or Desert, and the Nurse prefers the Hallow. Each NPC has specific biome preferences, so check the Terraria wiki for a full list. Next, consider their neighbors. NPCs have preferred neighbors and disliked neighbors. For example, the Arms Dealer likes the Nurse but dislikes the Steampunker. Pairing NPCs with their preferred neighbors and keeping them away from disliked ones will boost their happiness.

To maximize happiness, you can create small towns in different biomes. For example, build a Forest town with the Guide, Merchant, and Zoologist, as they all like the Forest and get along well. In the Desert, place the Arms Dealer and Nurse together, as they like each other and the Desert biome. In the Snow biome, the Mechanic and Goblin Tinkerer make a good pair. Spread out your NPCs across these towns to ensure they are in their preferred biomes and near their preferred neighbors.

When building these towns, make sure each NPC has their own house. Avoid stacking too many NPCs in one area, as overcrowding can reduce happiness. Use the Pylon system to connect these towns, allowing for fast travel between them. To unlock a Pylon, you need at least two NPCs in a biome with high happiness. Once unlocked, you can place the Pylon in the town for easy access.

Resource requirements for building these towns include wood, stone, and other basic materials for constructing houses. You may also need biome-specific blocks to create the right environment. For example, use Sandstone Blocks in the Desert or Ice Blocks in the Snow biome. Crafting stations like the Sawmill and Workbench are essential for creating furniture and walls.

Common mistakes to avoid include placing NPCs in disliked biomes or near disliked neighbors. For example, placing the Truffle in a non-Glowing Mushroom biome will make him unhappy. Another mistake is overcrowding, which can lead to reduced happiness even if the NPCs are in their preferred biome. Always ensure each NPC has their own space.

Advanced techniques include creating hybrid biomes to satisfy multiple NPCs. For example, you can create a Hallow Desert biome by spreading Hallow blocks in the Desert. This allows NPCs who like the Hallow and Desert to live together. Another technique is using the Clentaminator to change biomes quickly, allowing you to adjust the environment as needed.

In terms of class and equipment, the happiness system does not directly affect combat or progression. However, having happy NPCs can save you money on items and make travel easier with Pylons. This can indirectly help with resource management and progression.

Specific examples include setting up a Forest town with the Guide, Merchant, and Zoologist. Build three separate houses in the Forest biome, ensuring each NPC has their own space. Place the Guide next to the Zoologist, as they like each other. In the Desert, build two houses for the Arms Dealer and Nurse, placing them next to each other. In the Snow biome, create a town for the Mechanic and Goblin Tinkerer, ensuring they are close but not overcrowded.

By following these strategies, you can maximize NPC happiness, reduce item prices, and unlock the Pylon system for fast travel. Proper planning and resource management are key to creating a thriving town system in Terraria.